Yeah I dont think my raid is bad. We are 6/12 heroic 25 and 10/12 heroic 10. And we still have bosses up this week.
Initial threat is an issue. You have to be able to keep adds for specific fights. Princes is a great example... people are going to go nuts and charge generally runs you right past the boss. Getting raging spirits for LK is another example. Having the ability to climb the threat meter as a warrior for Heroic Lady Deathwhisper is another. Missing and getting parried there is terrible when you have to get to 2nd place and you dont have a ton of rage. Adds on Dreamwalker.... they have to be BURST down... but you have to pick up 2-3 at once. You simply cant afford to miss. In MANY of these situations, you cannot count on a misdirect or a ToTT.
Saying threat is only an issue for bad raids is pretty short sighted. Threat, like any other component in the game, must be managed. If the game was all Festergut fights, your analysis might be correct. But its not.... and there is a place for threat stats for tanks.
As a matter of fact, what kind of raid dps DOESNT put some kind of pressure on tanks? If you have guys destroying meters (like in my guild), you better be thinking about threat.